We will continue to study mechanisms by which the ciliary epithelium and aqueous outflow channels maintain intraocular pressure. The ciliary epithelium will be studied under conditions of injury and repair to learn about the transport properties of newly formed epithelia. Endogenous humoral and pharmacologic influences upon the turnover of aqueous inflow will be measured by clearance techniques. In addition, the ciliary epithelium will be examined in vivo by x-ray and angiography. Factors governing outflow resistance will be looked for by discovering the presence of enzyme systems for the synthesis and degradation of these substances, e.g. mucopolysaccharides. The mechanism of action of adrenergic drugs on intraocular pressure will be studied. An attempt will be made to isolate adrenergic receptors. Mediators associated with the irritative response, especially miosis and hyperemia, will be studied.